<template>
  <div>
    <table border="1" width="700" style="border-collapse: collapse">
      <caption>
        购物车
      </caption>
      <thead>
        <tr>
          <th><input type="checkbox" v-model="all" /> <span>全选</span></th>
          <th>名称</th>
          <th>价格</th>
          <th>数量</th>
          <th>总价</th>
          <th>操作</th>
        </tr>
      </thead>
      <tbody>
        <tr v-for="(item, index) in data" :key="index">
          <td>
            <input
              type="checkbox"
              :checked="item.checked"
              @change="$emit('changeCheck', index, !item.checked)"
            />
          </td>
          <td>{{ item.name }}</td>
          <td>{{ item.price }}</td>
          <td>
            <button type="button" @click="less($event, index, item.num - 1)">
              -
            </button>
            <span>{{ item.num }}</span>
            <button
              type="button"
              @click="$emit('changeNum', index, item.num + 1)"
            >
              +
            </button>
          </td>
          <td>{{ item.num * item.price }}</td>
          <td>
            <button type="button" @click="$emit('deleted', index)">删除</button>
          </td>
        </tr>
      </tbody>
      <tfoot>
        <tr>
          <td>合计:</td>
          <td colspan="5">{{ total }}￥</td>
        </tr>
      </tfoot>
    </table>
  </div>
</template>

<script>
export default {
  props: {
    data: {
      type: Array,
      required: true,
    },
  },
  computed: {
    all: {
      get() {
        return this.data.every((item) => item.checked === true);
      },
      set(value) {
        this.$emit("allCheck", value);
      },
    },
    total() {
      const toalArr = this.data.filter((item) => item.checked === true);
      return toalArr.reduce((total, item) => total + item.price * item.num, 0);
    },
  },
  methods: {
    less(e, i, v) {
      if (v <= 0) {
        v = 0;
        this.$emit("changeNum", i, v);
      }
      this.$emit("changeNum", i, v);
    },
  },
};
</script>

<style scoped>
button {
  min-width: 24px;
  height: 18px;
  border: 1px solid #000;
  margin: 0 6px;
  padding: 0 8px;
  cursor: pointer;
}
</style>
